<html>
  <head>
    <title>deck.gl GeoJsonLayer (Polygon) Example</title>

    <script src="https://unpkg.com/deck.gl@^9.0.0/dist.min.js"></script>
    <script src='https://unpkg.com/maplibre-gl@3.6.0/dist/maplibre-gl.js'></script>

    <link href='https://unpkg.com/maplibre-gl@3.6.0/dist/maplibre-gl.css' rel='stylesheet' />
    <style type="text/css">
      body {
        width: 100vw;
        height: 100vh;
        margin: 0;
        overflow: hidden;
      }
      .deck-tooltip {
        font-family: Helvetica, Arial, sans-serif;
        padding: 6px !important;
        margin: 8px;
        max-width: 300px;
        font-size: 10px;
      }
    </style>
  </head>

  <body>
  </body>

  <script type="text/javascript">

    const {DeckGL, GeoJsonLayer} = deck;

    const COLOR_SCALE = [
      // negative
      [65, 182, 196],
      [127, 205, 187],
      [199, 233, 180],
      [237, 248, 177],

      // positive
      [255, 255, 204],
      [255, 237, 160],
      [254, 217, 118],
      [254, 178, 76],
      [253, 141, 60],
      [252, 78, 42],
      [227, 26, 28],
      [189, 0, 38],
      [128, 0, 38]
    ];

    const geojsonLayer = new GeoJsonLayer({
      data: 'https://raw.githubusercontent.com/visgl/deck.gl-data/master/examples/geojson/vancouver-blocks.json',
      opacity: 0.8,
      stroked: false,
      filled: true,
      extruded: true,
      wireframe: true,

      getElevation: f => Math.sqrt(f.properties.valuePerSqm) * 10,
      getFillColor: f => colorScale(f.properties.growth),
      getLineColor: [255, 255, 255],

      pickable: true
    });

    new DeckGL({
      mapStyle: 'https://basemaps.cartocdn.com/gl/positron-nolabels-gl-style/style.json',
      initialViewState: {
        latitude: 49.254,
        longitude: -123.13,
        zoom: 11,
        maxZoom: 16,
        pitch: 45
      },
      controller: true,
      layers: [geojsonLayer],
      getTooltip
    });

    function colorScale(x) {
      const i = Math.round(x * 7) + 4;
      if (x < 0) {
        return COLOR_SCALE[i] || COLOR_SCALE[0];
      }
      return COLOR_SCALE[i] || COLOR_SCALE[COLOR_SCALE.length - 1];
    }

    function getTooltip({object}) {
      return object && `Average Property Value
        ${object.properties.valuePerSqm}
        Growth
        ${Math.round(object.properties.growth * 100)}`;
    }

  </script>
</html>